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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Yoshiaki Oka, Ichiroh Yanagisawa, Shigehiro An, Shun-ichi Miyasaka, Tomonori Hyodo
Nuclear Science and Engineering | Volume 76 | Number 2 | November 1980 | Pages 119-136
Technical Paper | doi.org/10.13182/NSE80-A19445
Articles are hosted by Taylor and Francis Online.
Reaction rate and dose rate distributions due to streaming o f neutrons and gamma rays were measured in the nearly cubical cavity and in the ducts leading to the cavity at the fast reactor YAYOI. The experimental configuration was arranged in a way that streaming through the ducts occurred only after scattering in the cavity. This was done by making the duct axes perpendicular to the source radiation from the reactor core. The spectrum of the source was modified from fast to thermal by putting moderators in the beam hole of the core assembly. The spatial distribution of the neutron reaction rates and gamma-ray dose rates in the cavity is almost flat except for a small decrease at the wall. The cadmium ratios at the duct inlets and the attenuation profiles in the ducts are almost identical irrespective of the spectrum of neutrons entering the cavity. The two-dimensional discrete ordinates transport calculation by TWOTRAN-II has shown that although the ray effect is observed in the fast neutron flux distribution in the cavity, the calculated results agree rather well with the experimental distributions in the cavity and with the streaming in the ducts with regard to the results measured with the l/v type neutron detectors. Also, for the gamma rays the agreement is rather good between the calculation and the experiment.